初中数学七年级下册（573题）

---

下列方程组中，是二元一次方程组的是（）

A.\(\left\{ {\begin{array}{*{20}{l}} {x + y = 3} \\ {z + x = 5} \end{array}} \right.\)

B.\(\left\{ {\begin{array}{*{20}{l}} {x = y} \\ {2x + 3y = 7} \end{array}} \right.\)

C.\(\left\{ {\begin{array}{*{20}{l}} {x + \frac{1}{y} = 5} \\ {x + y = 4} \end{array}} \right.\)

D.\(\left\{ {\begin{array}{*{20}{l}} {x + y = 3} \\ {xy = 7} \end{array}} \right.\)

知识点：第八章　二元一次方程组

参考答案：B